Before you buy your first inventory: how much to order, and what to check first

The most expensive mistake a first-time seller makes is rarely the product idea. It is the first order: a thousand units of the wrong colour, a landed cost nobody worked out, or stock sitting in a warehouse while storage fees run.

Every question below can be answered on paper, before any money moves. That is the cheapest test there is.

Do you need inventory to start selling online?

Not always. Print on demand, made-to-order and pre-orders let you sell before you hold stock. But if you are building a brand around a physical product on Amazon, Walmart or your own store, you will need inventory sooner or later. The real question is how much, and what you should know before you buy it.

Seven decisions before you pay a supplier

1. Does it already sell? Search demand, competitors with steady reviews, a trend that is rising rather than spiking. A product with no competition usually has no market.
2. Why would anyone pick yours? Read the one- to three-star reviews of the top sellers. Your version has to fix something buyers complain about.
3. What does it cost landed? The supplier’s price plus freight, duty, brokerage, packaging and prep.
4. What is left after fees and ads? If the margin only works with no advertising, it doesn’t work.
5. Is it allowed, and is it safe? Children’s products, batteries, cosmetics and anything that touches food can need testing first. In Canada, labels may need English and French.
6. Which version, and which channel first? One variant, one channel, where demand is clearest.
7. What happens if it doesn’t sell? Decide your way out, and the most you are prepared to lose, before you order.

What does one unit really cost?

Here is an illustrative product selling at C$34.99, with round numbers. The supplier quotes C$6.00. Freight, duty and brokerage, packaging and prep take the landed cost to C$9.00. The platform fee, fulfilment, the ad cost of each sale and a returns allowance take the rest:

Three warning signs: a landed cost above about a third of the selling price, profit per unit smaller than the ad cost per sale, or a margin that only works at a price above the top sellers’. If one unit doesn’t make money on paper, more units won’t fix it.

How much inventory should you buy for your first order?

Big enough to give you a real answer, small enough that a wrong answer doesn’t end the business. Work it out in five steps:

1. Monthly sales, honestly. Take the lower estimate for similar listings and halve it. A new listing has no reviews yet.
2. Time to restock. Production, shipping and warehouse check-in, in weeks.
3. Units to cover it. Monthly sales times months to restock, plus a small buffer.
4. The supplier’s minimum. Ask for a smaller first order at a higher unit price. Many factories agree.
5. Cash tied up and the most you could lose. Units times landed cost, plus samples, photos and launch ads, minus what clearance would bring back.

In the example: similar sellers move about 300 a month, so plan on 150. Restocking takes about ten weeks, so 150 × 2.5 plus a buffer of 75 is 450 units. The factory’s minimum is 1,000, but it agrees to 500 at a slightly higher price. That ties up about C$6,000 in all, with a worst case of around C$4,000 if clearance brings back C$2,000.

Go, test small or stop

Write down your lines before you order, not after the stock arrives.

• Go: all seven decisions answered with evidence and a margin that survives ad costs. Order two to three months of the honest sales estimate.
• Test small: demand is real but one answer is weak. Buy the smallest batch the supplier accepts, with one question, one target and a 60-day deadline.
• Stop: no proof of demand, no margin, or a safety question you can’t answer. The next product will cost less than this loss.

Have the product checked before you pay for it

You can work through all of this on your own. If you would rather have it answered with real data before any money leaves your account, that is what our product analysis does: demand and search trends, competitors and their reviews, landed cost and margin channel by channel, safety and marketplace flags, and a clear verdict with a first-order size. It costs far less than a first order that goes wrong.

See the format in our free analyses of a UV-C toothbrush sanitizer holder and food squishies, or book a free call and bring your product link or supplier quote.

Questions first-time sellers ask

Ready to find the factory? Read how to find a manufacturer for your product, or see how we launch a new online business with you.